b gury jr



Sept. 1'5, 1942. J, B. GURY, JR

` SHARPENER FOR CLOTH CUTTING MACHINES 1941 :s sheets'sheet 1 Filed March 3l f//5 4T To RME )4 Sept. 15, 1942.

J, B. GURY, JR 2,295,654

SHARPENER FOR CLOTH CUTTING MACHINES Filed March 31, 1941 s sheetsvsheet 1 Sept. 15, 1942. J. B. GURY, JR 2,295,654

SHARPEI-IER FOR CLOTH CUTTING MACHINES U Filed Mrch :51, 1941 :s sheets-sheet 2 Sept. 15, 1942. J. B. GURY. JR

SHARPENER FOR CLOTH CUTTING MACHINES 3 Sheets-Sheet 5 Filed March 3l /M/FA/TOB JOHN E. 60E); Je, y v VM f//S #Troy/ver Patented Sept. l5, i942 maar narran stares garant tries SHARFENER FR CLTH CUTTING MACHINES John B. Gary, Jr., Richmond Heights, Mo., as-

signer to J. B. Gury Mf 10 Claims.

The present invention relates to sharpening mechanism in cloth cutting machines wherein a vertically reciprocating blade is employed.

The object of this invention is to provide an efcient Sharpener for a cloth cutting machine of the type which has a vertical reciprocating knife.

The present invention includes improved means by which Such a Sharpener may be driven by the motor of such a machine. It includes means by which the motor is connected automatically to drive the Sharpener when the pressure foot bar is placed in lowermost position.

Improved driving mechanism is provided by the use of extended splined shafts so that the Sharpener is driven while it is moved vertically along the knife.

The Sharpener is so arranged that the maximum of the driving mechanism is away from the Sharpener. Abrasive materials from the Sharpener have a tendency to lodge on adjacent parts and cause troublesome wear, if those parts are such as to require close fitting.

Novel sharpening mechanism including noncircular resilient pulleys for abrasive belts is provided which gives the best results for a knife of the character herein and most nearly simulates the edge provided when a knife is sharpened manually by a skilled operator.

Other objects will be apparent from the following detail description of an embodiment of this invention, taken with the accompanying drawings.

Similar reference characters designate like parts throughout the drawings, in which- Fig. i is a side elevational view, partly in section, cf a cloth cutting machine .with my improved blade sharpening mechanism mounted thereon in operative position;

Fig. 2 is a Vertical sectional view line E f, of Fig. l;

Fig. 3 is a front'elevation of Fig. l, the lower portion being broken away;

Fig, 4 is a vertical sectional vi'ew on the line 4 4, Fig. 3, illustrating clutch details;

Fig. 5 is a vertical sectional view on line 5 5, Fig. 3, illustrating a bearing arrangement and helical gear mounting;

ig. 6 is a horizontal section on line 3, en an enlarged scale;

Fig. 7 is a similar View on line `i, Fig. 3, illustrating the means whereby the presser foot bar is held stationary during sharpening and cutting operations;

Fig. 8 is a plan or" the sharpening mechanism taken on 5 6, Fig.

g. Co., St. Louis, Mo., a

in operative position, the view being taken on line 8 8, Fig. 3;

Fig. 9 is a fragmentary View similar to Fig. 3, on an enlarged scale showing the sharpening mechanism clamped in open position;

Fig. l0 is a plan view of said mechanism, the view being taken on line lil-IU, Fig. 9, and showing in detail a clamping arrangement;

Fig. l1 is a sectional view on the line Il l I, Fig. 9;

Fig. l2 is a bottom plan view of the sharpening assembly, the view being indicated by line I2 l 2, Fig. 3;

Fig. 13 is a fragmentary View similar to Fig. 1, illustrating the sharpening assembly clamped in its inoperative position immediately following a sharpeniniCr operation;

Fig. le is a vertical section on line Iii-i4, Fig. 10; Y v

Fig. l5 is a similar view on line |5-I5, Fig. 8;

Fig. 18 isan enlarged fragmentary Viewl similar to Fig. 8, illustrating a condition obtaining at one stage of the sharpening operation;

Figs. 17 and 18 are respectively a plan and a lside elevation of a resilient pulley member as it appears before its adaptation to the present invention; and

Figs. 19 and 20 are similar views of a pulley hub illustrative of one of several configurations contemplated.

With particular reference to Fig. 1, the sharpening assembly A is Shown embodied in a cloth cutting machine B of well known design.

The base C thereof, is supported by rollers (not shown) whereby the machine may be oprated along a flat surface supporting a lay of cloth or similar material.

A lvertically reciprocating cutting knife D, slidably supported in a column or standard E extending upwardly from said base, is operated by means of a crank pin F and associated connecting rod G, the source of power being a motor H having a fly-weight H1, xed to its shaft J.

During cutting operations the position of the vertically adjustable bar K, which carries the presser foot member M, is manually determined by means of the locking and releasing linkage N as shown, or by similar means. A description of the expedient illustrated will appear hereinafter. An appropriate handle is provided for manipulating the machine.

Excluding the sharpening mechanism A, machines of the character thus far described are well known in the art, and further detailed description is deemed unnecessary.

The sharpening assembly A is slidably mounted on the presser foot bar K in such manner that the blade D may be sharpened from end to end. Said assembly includes a carriage I, provided With a hub portion 2 through which the bar K extends, said hub having a polygonal opening 3 slightly larger than the exterior contour of said bar, the latter also being polygonal in horizontal cross section.

A thumb and index finger extension 4 is integral with said carriage, as are also two depending tubular cylindrical portions 5. Rotatively sleeved on each of the latter is the hub portion 6 of a pair of twin plates 'I, each provided with an opening through which passes a hollow shaft 8 secured against rotation by a nut 9 (Fig. 14).

Mounted on each shaft B between a shoulder I thereon, and properly spaced by a sleeve II held in place by a cap screw I2 as shown, is a pulley construction generally indicated by the numeral I3. Each pulley includes a non-circular annular tire I4 of resilient material having a plurality of spaced apertures I5, for reasons later explained. Obviously any one of a number of resilient materials may be employed, but I have found by tests that synthetic rubber rings, such as illustrated in Figs. 17 and 18, are most satisfactory. It is noted that the outer periphery of such rings is convex as at I6, and that prior to mounting on the sharpening device the rings are circular.

An inspection of Figs. 11 and 14 is invited to clarify the manner in which the circular body of Fig. 1'7 is mounted on the Sharpener A, so that it assumes a non-circular configuration in accordance with my invention.

At II is shown a rectangularly contoured metal hub, the distance between whose diametrically opposed corners is slightly greater than the inside diameter of a ring or tire I4. Said' corners are rounded as shown at I8. The resilient circular body I4 is forcedA over a member I8 and clamped in place between an annular flange I9 thereon and a circular plate 20 secured to the member I1 by removable screws, as shown in Fig. 14. An additional spacer sleeve 2| of proper length is interposed between the upper surface of said member and the aforementioned shoulder I0. As is apparent each pulley structure I3 is freely rotatable on its shaft 8.

With reference to the resilient pulley bodies it is to be noted that the deformation thereof is slight. The rounded corners I8 facilitate the entry of the polygonal member, as do the apertures I5, but neither of them is indispensable. The embodiment shown however is preferable, since the rounded corners I8 eliminate any tendency to cut into the body and the perforations I increase its resiliency. Attention is also directed to the ease with which a defective or worn out pulley may be removed and repaired or replaced, by removal of the screw I2 and the sleeve I have found by experiment that the best results are obtained with my Sharpener when nonidentical peripheries are provided in an associated pair of pulleys. Thus, as shown in Fig. l1, one pulley body I 4 may be mounted on a pentahedral member I'Ia, thereby producing an ideal arrangement. To maintain the pulleys in proper spaced relationship their supporting plates 'I are provided with semi-circular intermeshing racks 22, movement of the plates being had by manipulation of a lug or finger piece 23. The finger piece or lug 23 is formed integrally with one of a pair of abutments 24, one of which is clamped on each plate 'I by the nut 9. The abutments 24 cooperate with spring-pressed ball devices 25, xed in the carriage I and adapted to maintain the arms 1 and the pulley assemblies in a stationary out-of-the-Way position when the Sharpener is not in use, as shown in Fig. 10.

Novel means to drive the sharpening mechanism A simultaneously with the knife D is provided. It includes a disc 25 driven by the motor shaft J, and a disc 21 integral with a, boss 28, the latter having an integral helical gear 2S formed thereon, all located in the upper portion of a housing 3&1 secured to the motor by screws 3l. The two discs form a clutch automatically disengaged during cutting operations, and also automatically engaged during sharpening operations by means to be later described.

As best shown in Figs. 1, 2 and 6, the motor driven disc 25, knife reciprocating rod G and flyweight are connected by crank pin F, with suitable spacers being provided where necessary to maintain proper alignment. The disc 26 is provided centrally thereof with a circular recess to accommodate the head of a screw 33 threaded in the end of a shaft 34, the head of the screw forming an end bearing to hold the disc 21 on that shaft. The shaft 34 is journalled in a sleeve 35 which is press-fitted or otherwise fixed within the boss 28.

During cutting operations, the disc 2'I is disengaged from the disc 26 by means of a leaf spring assembly 36, later to be described. At such time the disc 25 merely revolves about the head 33 and the presser foot bar K occupies an elevated position, such as suggested by the broken lines in Fig. l.

The leaf spring assembly, as shown in the drawings, is composed of three components, two of which are fixed in the housing 3B by means of a screw 31. One component designated 38 bears against the other designated 39 normally forcing it to the right, as shown in Fig. 4. The shaft 34 is firmly attached, as by riveting, to the upper end of the spring leaf S9. 'Ihis permits a slight space to obtain between the clutch disc when the third leaf spring 4I! is free by reason of the elevated position of the bar K and its clutch operating elements, generally indicated at 4I.

To facilitate clutch engaging and disengaging operations, the member 4B is provided with an off-set portion 42, which, as shown, lies in the vertical path of a roller 43, rotatable on a pin 44 supported in th'e bifurcated ends 45 of a horizontal element 45 clamped in predetermined position on the bar K by a screw 4l. Since Fig. 4 clearly illustrates the engaged position of the clutch, it is thought unnecessary to specifically illustrate the disengaged position.

Necessarily, in order to sharpen the knife D, the presser foot occupies the lowered position shown in Fig. 1, while during cutting operations it occupies an elevated position. No claim is made to the structure N herein illustrated by which' this is accomplished; and which includes a manually operable lever arm 48 adjacent the handle O, pivoted at 49 and having a bifurcated portion 5@ engaging a pin 5I of a sliding bolt 52 adapted to enter notches 53 formed in bar K. A spring 54, or other expedient, may be employed to maintain the bar in desired position. The bar K is raised and lowered manually by an integral extension 55 of the member 45.

The motor shaft J, fly-weight H', disc 26, disc 2'! and helical gear 29, all rotate clockwise. However it is necessary for the pulley assemblies I3 to rotate in opposite directions to one another, and each pulley is independently driven, dual drive shafts 56 being employed. The shafts 58 are rectangular in cross section as shown, or splined to have a vertically sliding t within a pair of helical gears 57 as well as within their integral, depending exteriorly cylindrical portions 58.

The helical gears 5l disposed at right angles to the gear 29 loosely intermesh with the latter, so that when the clutch engaging leaf spring assembly 3S is free the disc 26 automatically effects a separation between itself and the disc 21, Each sleeve 58 is rotatably supported in bushings 59 and suitable openings 68 are provided in the housing 38 through which the dual shafts 56 eX- tend. Protective elongated caps 8l cover said openings and the upper ends of said shafts.

An inspection of Figs. 5, 6 and 7 will aid in clarifying the foregoing description. For assembly purposes the housing 3i! is split along the vertical center line of the dual shafts and has a cover plate portion 82. Screws 63, as shown, maintain the housing parts in assembled relation.

The dual driving shafts 55 are squared or splined from their upper extremities downwardly to an integral collar fifi, thence circular as at 85 with their lower extremities being externally threaded as at 58. A pulley 81 is mounted on the hub portion E of each plate l, preferably in different elevations as shown in Fig. l5.

One of said pulleys, that on the left, is driven by its shaft 56 through the medium of a disc nut 68 internally threaded to engage th'e threaded end 66 of said shaft. The disc nut is provided with an aperture 68a through which extends a pin 69 integral with the pulley. A lock nut lil and a spacer 'Il complete the mounting arrangement.

The right hand construction is similar except that the spacer member 'l la is positioned beneath the pulley and has two pins 69a, one of which enters the aperture 68a of the disc nut 68, while the other enters an appropriate depression in the pulley 6l. In either arrangement a positive drive is obtained.

The described and illustrated arrangement is preferable to facilitate assembly as well as replacement of the non-metallic pulley facing l2, should it become worn.

A chamber i3 wherein suitable lubricant retaining and dispensing material is contained has a cover lll, removably secured to the carriage i by a screw l5. The lubricant may be replenished from time to time through an opening 'i5 in said cover lli, with ports ll supplying the lubricant to the moving parts.

A pair of endless iieXible belts i8 whose eX- terior surfaces are abrasively coated as at 'i9 connect the drive pulleys 6l with the pulleys I3. Replacement of the belts is obviously simple. Due to the resiliency of th'e belt contacting material of the respective pulleys, no slack take-up contrivance is necessary to maintain the belts taut.

It should now be apparent that with the clutch arrangement described the Sharpener assembly may be caused to function simultaneously with the vertical reciprocation of the blade D, when sharpening of the latter is in order.

Novel means are provided to secure the entire sharpening assembly A in an out-of-the-way position during cloth cutting operations. The preferred means, as illustrated more particularly in Fig. l0, includes a clamping member 88, split at 8! and secured by a screw 82 to a plate 83, which in turn is secured to the housing 30 by screws 84. The clamping member 88 has a bore 85 slightly larger than the h'ub 2 of the carriage I. A bolt 86 threaded into one portion of the split clamp as at 87, and passing freely through a transverse opening 88 in the other portion thereof, is provided with a ixed manually operable handle 89 and a collar 9d engaging the outer surface of the clamp, whereby the hub portion `2 may be clamped or released as desired.

The aforementioned Sharpener assembly locking and releasing means is not deemed to require further description, since it is obvious manipulation of the handle 89 away from the machine releases the Sharpener assembly, and the opposite manipulation thereof will clamp said assembly in elevated position during cutting operations.

When it is desired to sharpen the blade, the operator proceeds as follows, without shutting of the power: The assembly clamp is released by turning the handle 89. Then, releasing the locking mechanism N with one hand, the pressure foot bar K, with the Sharpener assembly A thereon, is lowered by grasping theI member 55, secured to the bar K, with the other hand. When the bar is brought to lowermost position, the roller t3 (Fig. 4) engages the spring 42, thereby connecting the motor to the Sharpener. Then by grasping the finger piece 23 (Figs. 8, 9 and 10) the arms or plates 'l' are moved from open position (Fig. 9) to operative position (Fig. 8), and by means of the nger extension 4, the Sharpener assembly A is reciprocated upwardly and downwardly while the belts engage the opposite sides of the blade D.

Because of the resiliency and non-circularity of the pulleys i3, a more or less intermittent pressure is applied to opposite sides of the blade at separated points. Since one pulley is mounted at a higher elevation than the other there is never any tendency of the pulleys to bind. Because the pulleys are driven toward one another, no device of any kind is required to maintain the belts in constant yielding engagement with the opposite sides of the knife. The belts 18 take care of this since the pull is on the inner stretches thereof tending at all times to bring the pulleys inwardly against the blade.

As previously described, each pulley has a number of protuberances caused by the insertion of the member l'i in the resilient member ld. It has also been noted that a pair of pulleys having a different number of such protuberances will obtain the best results. The somewhat increased pressure app-lied when that portion of a belt covering a protuberance engages the blade, has a tendency to momentarily effect the disengagement of the other belt, resulting in a bouncing and sweeping action.

Fig. 8 illustrates this condition, the left hand pulley being in the act of rebounding into engagement with the blade. This view is in perfect scale with the remainder of the views, the only exaggeration being the space X, which in reality is so slight as t0 defy proper illustration. Shown on a larger scale in Fig. 16 is the condition obtaining a moment later, when a protuberance on the left hand pulley is in the act of eiTecting a momentary disengagement of the right hand pulley and its belt. The racks 22 are tted rather loosely to each other so some independent movement of the plates 7 is permitted.

The irregularity of the pulleys results in a 

